Maintaining pavement at an airport is critical to keeping the airport at full capacity and maintaining a cost-effective operation. The Government Accounting Office (GAO) stated in a report in 1998 (http://www.gao.gov/archive/1998/rc98226.pdf, incorporated herein by reference) that pavement is in poor condition requires much more drastic repair than pavement maintained in good condition. This increase in repair costs varies between two to three times more than it would have cost to repair pavement that was in good condition. Monitoring conditions of pavement is critical to decision makers at an airport who must decide when to allocate recourses to effectively maintain airport operational status.
The GAO report also recommended that the FAA consider options for developing a pavement management system to track the condition of the runways so that repairs could be conducted in a timely and cost-effective manner.
Although not a direct noise monitoring responsibility, pavement management has a strong environmental component and many airport offices dealing with noise management also have to deal with pavement management issues. The software and system of the present invention was developed after discussions with existing AirScene clients, as well as potential new clients where pavement age and condition has become both an environmental and capacity issue.
Runway maintenance issues may involve airport staff from accounting, operations, noise and air quality (environmental), air traffic control, and many others. Gerald L. Dillingham, the GAO's Director of Physical Infrastructure, related the problems associated with building and maintaining runways and the environment in his testimony before Congress in October 2000 (http://www.gao.gov/new.items/d0190t.pdf, incorporated herein by reference).
Runways requiring maintenance are often closed so that those maintenance operations can be completed. These closures normally occur at night to minimize the impact on airport operations. Aircraft may have to be diverted to non-preferred runways during these maintenance periods and thus causing aircraft to over-fly areas rarely seeing activity during that time period. These flyovers may generate a number of noise and other complaints and more severe responses if the closures are for longer durations.
The accepted practice for determining the conditions of the pavement at airports is a manually intensive and time-consuming process. Trained airport staff or consultants must manually inspect and grade the pavement on a scale from 0 to 100. This rating is known as the pavement condition index (PCI). Semi-automated processes have been developed using a variety of technologies to scan pavement and automatically rate the pavement on the PCI scale. These systems can process more pavement area in a shorter time, however runways and pavement undergoing analysis must be closed and clear of traffic during the inspection, as equipment to inspect the pavement must be driven over the runway.
Software and systems do exist to help an airport manage its pavement based on the results of these subjective inspections. The most popular program for logging the PCI was developed by the Army Corps of Engineers under contract from the FAA. The software is known as “Micro PAVER” and is available the Corps (http://www.cecer.army.mil/paver/, incorporated herein by reference) for a nominal fee. Other software is available on the commercial market and includes AIRPAV (http://www.airpav.com/airpav.htm, incorporated herein by reference) from Eckose/Green. However the Micro PAVER software is the most popular system presently in use at most airports.
Consultants such as C.T. Male Associates, working with GIS software company ESRI, have developed their own semi-automated systems (See, e.g., http://cobalt.ctmale.com/AirportGIS.htm, incorporated herein by reference, and http://www.esri.com/news/arcnews/summer02articles/albany-airport.html, also incorporated herein by reference). This system was developed for an airport in Albany NY. The system uses wireless hand-held computers with GPS to categorize and log the PCI. Systems of this type are also under development at other airports including a system currently under development by Aeroware (http://www.aeroware.com, incorporated herein by reference) at a general aviation airport in the western United States.
This type of quasi-automation saves some time and labor but still requires physical inspection and closure of the runway, taxiways, or ramp areas. These systems are useful for predicting maintenance needs only if supplied regularly with PCI survey data and data from quantified defects analysis. Acquiring the type of data that these systems need is time consuming, costly, and is labor intensive.
Other products on the market such as the product called A.I.R.P.O.R.T.S. by Dynatest (http://www.dynatest.com/software/airppms.htm, incorporated herein by reference) also rely on manual measurements and tests done on the physical pavement to assess the condition. Dynaport's PMS product can use visual PCI data, structural data from the Heavy Falling Weight Deflectometer, skid resistance data, and functional data from the Road Surface Profiler. All of this data is acquired in the field.
In order to be useful as a pavement condition assessment and prediction tool, these types of systems rely on frequent measurements of the physical characteristics of the pavement in order to determine when to repair the pavement. This type of physical inspection-based system has become popular in the absence of autonomous techniques.
Since airlines were deregulated, the number of flights at many airports has increased dramatically. Dismantling the hub-and-spoke routing system may result in the more direct point-to-point flights, which may result in more takeoffs and landings at smaller regional airports, which have less manpower an infrastructure available to monitor pavement conditions on a regular basis.
In addition, the advent of larger airliners such as the Boeing 777 and the Airbus A380 may result in greater wear in runways and taxiways due to the increased weight of these newer aircraft. Merely counting landings and takeoffs of aircraft may be an insufficient indicia of pavement wear, as these heavier aircraft may cause many times the wear of more traditional, smaller aircraft.
Moreover, as airports expand, many extended taxiways may be in use. Depending upon prevailing wind conditions, airport and terminal layout, the amount of use of each taxiway and runway may vary considerably. Thus, for example, if prevailing winds at an airport are consistently from one direction, one runway (or set of runways) may experience substantially more wear than other, lesser-used runways. Repaving all runways and taxiways after a predetermined amount of time or after a predetermined number of takeoff/landing cycles may represent an inefficient use of airport maintenance resources, as some runways and taxiways may experience considerable wear, while others are still in usable condition. Moreover, using such arbitrary criteria to determine pavement condition may fail to detect pavement degradation in some frequently used taxiways and runways.
Thus, it remains a requirement in the art to provide a means for accurately determining pavement conditions at various parts of an airport to provide an computerized model of pavement conditions to assist airport managers in making effective determinations of which areas of the airport pavement infrastructure to repair, and when to make such repairs.